CALL POKE

CALL POKE

Writes a value directly into memory

Category: Special

Syntax
Arguments
Details
See Also

Syntax

CALL POKE(source,pointer<,length>);

Arguments

source

specifies a SAS expression that contains a value to write into memory.

pointer

specifies a numeric SAS expression that contains the virtual address of the data that the CALL POKE routine alters.

length

specifies a numeric SAS expression that contains the number of bytes to write from the source to the address indicated by pointer. If you omit length, the action that the CALL POKE routine takes depends on whether source is a character value or a numeric value:

If source is a character value, the CALL POKE routine copies the entire value of source to the specified memory location.
If source is a numeric value, the CALL POKE routine converts source into a long integer and writes into memory the number of bytes that constitute a pointer.
Operating Environment Information: Under OS/390, pointers are 3 or 4 bytes long, depending on the situation.

Details

CAUTION:: The POKE routine is intended only for experienced programmers in specific cases. If you plan to use this routine, use extreme care both in your programming and in your typing. Writing directly into memory can cause devastating problems. This routine bypasses the normal safeguards that prevent you from destroying a vital element in your SAS session or in another piece of software that is active at the time.

If you do not have access to the memory location that you specify, the POKE routine returns an "Invalid argument" error.

See Also

Functions:

ADDR

PEEK

PEEKC

POKE

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